I used IntelliJ to do some package renaming refactoring. I was confident that it was safe to do so, however, other parts of the code had changed when they should not have. Later on, I discovered the problem and fixed it. I used to avoid find/replace tools or grepping because it is dangerous as you can easily change parts that should not be changed.
you have to be careful all the time and avoid being deceived by automated smart refactoring tools. I learned that using unsafe find/replace carefully is better than using smart refactoring tools carelessly.